HTML5+CSS3做一个后台管理系统的侧边导航栏，点击三条杠，可以收起或展开侧边导航栏。收起时，图标变大，文本在图标下方，管理员头像右侧的欢迎语隐藏；展开时图标变小，文本在图标的右侧显示，管理员头像右侧的欢迎语显示。切换过程伴有过渡动画，右侧内容区可以放自己的内容。
效果：
源码：
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no">
<title>侧边展开导航栏</title>
<!-- 引入字体图标 -->
<link rel="stylesheet" href="https://cdn.staticfile.org/font-awesome/4.7.0/css/font-awesome.css">
<link rel="stylesheet" href="../css/25.css">
</head>
<body>
<div class="navbar">
<input type="checkbox" id="checkbox">
<label for="checkbox">
<i class="fa fa-bars" aria-hidden="true"></i>
</label>
<ul>
<li>
<img src="../images/1.png" alt="">
<span>欢迎您！管理员</span>
</li>
<li>
<a href="javascript:void(0)">
<i class="fa fa-home" aria-hidden="true"></i>
<span>后台首页</span>
</a>
</li>
<li>
<a href="javascript:void(0)">
<i class="fa fa-sitemap" aria-hidden="true"></i>
<span>商品列表</span>
</a>
</li>
<li>
<a href="javascript:void(0)">
<i class="fa fa-user-circle-o" aria-hidden="true"></i>
<span>用户列表</span>
</a>
</li>
<li>
<a href="javascript:void(0)">
<i class="fa fa-shopping-bag" aria-hidden="true"></i>
<span>订单列表</span>
</a>
</li>
<li>
<a href="javascript:void(0)">
<i class="fa fa-th-large" aria-hidden="true"></i>
<span>功能列表</span>
</a>
</li>
</ul>
<div class="main">
我是内容区
</div>
</div>
</body>
</html>
*{
/* 初始化 取消内外边距 */
margin: 0;
padding: 0;
}
body{
/* 溢出隐藏 */
overflow: hidden;
}
.navbar{
/* 相对定位 */
position: relative;
/* 100%窗口宽度 */
width: 100vw;
display: flex;
}
.main{
flex: 1;
height: calc(100vh - 43px);
position: relative;
top: 43px;
display: flex;
justify-content: center;
align-items: center;
}
#checkbox{
display: none;
}
.navbar label{
position: absolute;
top: 0;
left: 70px;
width: 100%;
height: 43px;
font-size: 30px;
color: #5a738e;
background-color: #ededed;
padding-left: 20px;
border: 1px solid #d9dee4;
cursor: pointer;
/* 加个动画过渡 */
transition: all 0.5s;
}
.navbar ul{
list-style: none;
width: 70px;
/* 100%窗口高度 */
height: 100vh;
background-color: #2a3f54;
transition: all 0.5s;
overflow: hidden;
}
.navbar ul li{
height: 70px;
margin-bottom: 10px;
}
.navbar ul li:first-child{
display: flex;
justify-content: center;
align-items: center;
padding: 0 10px;
}
.navbar ul li:first-child img{
width: 50px;
height: 50px;
border-radius: 50%;
}
.navbar ul li:first-child span{
/* 先把文字隐藏起来 */
display: none;
color: #fff;
/* 文字禁止换行 */
white-space: nowrap;
padding-left: 10px;
}
.navbar ul li a{
display: flex;
justify-content: center;
align-items: center;
/* 垂直排列 */
flex-direction: column;
width: 100%;
height: 100%;
color: #d1d1d1;
text-decoration: none;
}
.navbar ul li a i{
font-size: 25px;
margin-bottom: 10px;
}
.navbar ul li a span{
font-size: 12px;
white-space: nowrap;
}
.navbar ul li a:hover{
color: #fff;
background-color: #35495d;
}
/* :checked选择器是判断复选框是否被选中 */
/* +是相邻兄弟选择器，找到input的下一个兄弟label */
.navbar input:checked + label{
left: 200px;
}
/* ~也是兄弟选择器，但它可以找到隔了几代的兄弟 */
.navbar input:checked ~ ul{
width: 200px;
}
.navbar input:checked ~ ul li:first-child{
/* 将居中改为开头对齐 */
justify-content: flex-start;
}
.navbar input:checked ~ ul li:first-child span{
/* 文字显示 */
display: block;
}
.navbar input:checked ~ ul li a{
flex-direction: row;
justify-content: flex-start;
}
.navbar input:checked ~ ul li a i{
font-size: 18px;
margin: 0 15px 0 30px;
}
.navbar input:checked ~ ul li a span{
font-size: 14px;
}
